Apparatus for manufacture of container bodies



Feb. 24, 1970 ALSO KNOWN AS APPARATUS FOR MANUFACT Filed July 17, 1967 INVENTORS A. DEAN SMITH j a j ATTORNEY 6 1 5 t n W 6 am 9 .r A" 3 8 L Am mm mm HII T m SN M O s N F my E E D R U H T R A BY CORNELIS LANGEWIS J T Q J m A w rlmmw Feb 24, 1970 ARTHUR'ZIDEAN SMITH 3,495,756

- ALSO KNOWN AS A. DEAN SMITH ET AL APPARATUS FOR MANUFACTURE OF CONTAINER BODIES Filed July 17, 1967 2 Sheets-Sheet 2 INVENTORS A. DEAN SMITH CORNELIS LANGEWIS ATTORNEY 3,496,756 APPARATUS FOR MANUFACTURE OF CONTAINER BODIES Arthur Dean Smith, also known as A. Dean Smith, San Lorenzo, and Cornelis Langewis, Walnut Creek, Calif., assignors to Kaiser Aluminum & Chemical Corporation, Oakland, Calif., a corporation of Delaware Filed July 17, 1967, Ser. No. 653,951 Int. Cl. B21d 22/06 U.S. Cl. 72432 21 Claims ABSTRACT OF THE DISCLOSURE A press apparatus of the draw and iron type for manufacturing seamless container bodies, wherein a separate punch means is attached to each side of a common actuating piston and with the piston being driven in an improved manner and wherein the punch means is resiliently connected to and biased in an improved fashion relative to the actuating piston. The aforesaid driving arrangement provides an exceptionally smooth and reliable stroking of each of the punch means. The aforesaid connection andbiasing of the punch means relative to the actuating piston provides an advantageously safety feature for the apparatus whereby if an individual punch means for any reason becomes locked or frozen to its associated die means during passage of the punch means therethrough under the urging of the actuating piston, the punch means automatically becomes disengaged or uncoupled from the actuating piston so that the actuating piston can continue to freely reciprocate without deleteriously affecting the other working parts of the apparatus.

BACKGROUND OF THE INVENTION This invention relates to a press apparatus for producing seamless shells such as container bodies provided with a bottom and a sidewall formed integrally therewith. More particularly, it is concerned with a machine of the draw and iron type, wherein an improved overall driving means is provided for actuating a series of forming punches and rams as well as improved safety mechanisms for each punch of the machine in order to prevent injury to the machine in the event there is a jamming of a punch in the die elements of the tool pack with which the particular punch is cooperatively associated. In one embodiment of the invention, which will be described in detail hereinafter, the improved safety feature can be incorporated in a machine wherein a series of punches are attached to each of the opposing ends of a common actuating piston and rod means.

Although draw and iron press equipment analogous to that under consideration is disclosed and described in U.S. Patent 3,167,044 to Henrickson, and machine drives analogous to that proposed is disclosed in U.S. Patent 2,766,590 to Erwin et al., none of the devices of the aforesaid patents contemplated the manner of use of the improved punch drive mechanism in a press of the draw and iron type of the improved punch safety or fail-safe mechanism of the instant type whereby, upon jamming or freezing of the punch or ram in its associated and cooperating dies, the punch would be automatically disengaged from a common actuating piston. Use of the aforesaid features is significant in obtaining the reliable stroking and high speeds required to meet present day commercial can body production requirements, and to prevent serious damage to expensive equipment and extensive equipment down time when repairs are needed.

SUMMARY OF THE INVENTION Accordingly, it is a primary purpose of the instant States Pate t 3,496,756 Patented Feb. 24, 1970 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a broken elevational sectional view of a preferred embodiment of a double-acting draw and iron press of the instant invention with parts removed or broken away; FIG. 2 is an enlarged and broken cross-sectional view of a portion of the press of FIG. 1 when generally taken with the circumscribing line 2 of FIG. 1 and with the relative positions of disabled punches on one side of the apparatus to the remainder of the apparatus being shown; and

FIG. 3 is an enlarged sectional view of a poppet safety valve mechanism used in the apparatus of the instant invention.

With further reference to the drawing, a preferred embodiment of the apparatus of the instant invention generally comprises a main housing 2 made up of an upper casting A appropriately secured to a bottom casting B which is mounted in the floor of the building in which the press is installed. When the castings A and B are assembled, they form a series of outer compartments or chambers 4 and 8, a main chamber 6, a base 10, main sidewalls 12 and 14, and inner ribs 16 and 18.

The intermediate sections of outside walls 12 and 14 are cut away to provide stepped bores 20, which are aligned with similar bores 22 in the inner ribs 16 and 18. Twin sleeves 23 are appropriately anchored in the bores 20 and 22 and each sleeve is adapted to slidably receive one of the opposed segments 26 and 28 of the roughly cross-shaped driving piston or yoke disposed within main chamber 6 of the housing 2.

The interior 30 of each piston segment 26 and 28 is hollowed out preferably in a stepped fashion and each of the piston segments 26 and 28 is adapted to snugly fit and reciprocate within its associated sleeve 23. The central portion of driving yoke 25 is also hollowed out s as to accommodate a slide element 32 made up of two partially circular elements 33 which are coupled about a pin element 34 connected to a pair of crank arms 35 (only one of which is shown in dotted lines). Each one of the pair of arms 35 at their ends opposite their connection to the pin element 34 is affixed to a journal shaft 35 wherein one of the journal shafts 35' as illustrated in dotted lines in FIG. 1 is connected to and driven by a drive wheel 36 motivated in a conventional fashion by the motor M through the belt drive 37. The slide element 32 fits between sl des 38 of suitable material disposed within the hollowed-out portion of the double-acting driving yoke 25. Attached to each of the sidewall elements 12 and 14- of the housing 2 is a closure element or side cap 40 which can be made in the form of a casting. Each side closure element 40 by virtue of its configuration provides in combination with the sides 12 and 14, a large chamber or well 42 on each side of the apparatus for receiving operating fluid such as oil. The castings 40 are advantageously constructed so as to provide a cantilevered suspension or support arm 44 for tool pack assembly C made up of various die elements (to be described more fully hereinafter). It should be noted at this point that, although not shown in the drawings, the cantilevered suspension arm 44 for the left hand tool pack C and the left hand tool pack C per se are similar in construction and detail to the right hand tool pack C and suspension arm 44. Thus, a description of one of the arms 44 and one tool pack C and the various parts thereof on one side of the apparatus will sufiice for both arms 44 and their related tool packs C.

The upper portions of outside walls 12 and 14 and the upper portions of the inner ribs 16 and 18 are provided with a further series of aligned openings 50, 52, 54 and '56. These openings form a tunnel for an elongated tubular fitting or sleeve element 58. Located within sleeve 58 is a reciprocating elongated hollow piston rod 60. An actuating piston 62 is rigidly aflixed to the outer central portion of rod 60 and piston 62 is adapted to be reciprocated or cyclically driven in a balanced fashion by means of fluid introduced alternately into the opposing sides of the fluid chamber 64 which exists between sleeve 58 and hollow piston rod 60 on opposite sides of piston 62.

As indicated particularly in FIG. 2, each end of chamber 64 is in open communication with a separate opposing main fluid chamber 42 in the manner shown in the drawings whereby a closed fluid circuit is formed thereby and with yoke 25 and actuating piston 62 being disposed in different portions of this circuit. The upper portion of each chamber 42 adjacent sleeve 58 is closed off by means of a combination bearing and fitting 66 and gasket elements 68. These fittings and gasket elements 66 and 68, as indi cated in the drawings, fit within openings 67 in the outer end caps 40 and in between the outer caps 40 and the hollow piston rod 60, with rod 60 being adapted to freely slide within the bearings and fittings 66.

From the above it will be readily observed that as the crank elements or arms 35 connected to and operated by drive wheel 36 are rotated by wheel 36, slide elements 33 will move up and down the slides 38 of driving yoke 25 while at the same time forcing yoke 25 and the respective piston segments 26 and 28 thereof to reciprocate back and forth and at the same time cause fluid to course alternately out of and into one of the two main chambers 42, into and out of opposite sides of the fluid chamber 64 and against opposing sides of punch actuating piston 62 with the fluid in each chamber 42 acting in effect as a fluid coupling between piston segments 26 and 28 of yoke 25 and the actuating piston 62. Piston 62 under the urging of fluid directed against the various sides thereof will then effect corresponding movements or stroking of the hollow piston rod 60.

A further hollowed out piston rod 70 to which a piston 72 is attached is advantageously concentrically and telescopingly disposed within the hollow piston rod 60 on each of the opposing sides of the main driving piston 62. Inas much as the structure and function of each hollowed out piston rod 70 and piston 72 on each side of actuating piston '62 and the manner of attachment of each rod 70 to one or more rams on each side of the apparatus are all the same, a description of one such rod 70 and piston 72 and their associated elements will suflice for all such elements.

As indicated particularly in FIG. 2, each piston 72 is appropriately locked within a step 75 at the inner extremity of the hollowed out piston rod 70 by means of a lock ring assembly 75'. The opposing free end of each rod 70 is attached to a series of hollowed out forming rams 74 in the manner shown in FIG. 2 and each piston rod 70 is slidably disposed within a central opening in a combina tion bearing and closure cap 80 rigidly aflixed in a suitable fashion to each outer extremity or end of the main hollow piston rod 60. An outside cap and guard 82 is secured to each inner cap 80 by a series of appropriate counter-sunk bolt elements 84 which are insertable in aligned openings in caps 80 and 82.

As indicated particularly in FIG. 2, each cap 80 is further provided with a series of intercommunicating bores 85, 86, 87 and 88 and partially angled shaped bore 88'. Bore 88' is normally closed by a removable plug 89 at the top and a bolt 84 at one end. Bore 88 communicates directly with the central hollowed section 89' of fitting 80 and acts to further connect hollowed out section 89 with bore 86. Bore 86 contains a spring 90 used to bias the ball check valve 91 against its seat provided in an apertured plug 92 which fits within bore 85. The aperture of the plug 92 in bore is adapted to communicate directly with a further passageway 94 in hollow piston rod 60, which ultimately leads to the annular chamber 96 provided between hollow piston rod 60 and the flanged ring 98 interposed between fitting 66 and hollow piston rod 60 and fitting within a further ring 98'. A compressed air port 100 in ring 98 and connected to a suitable source of air pressure (not shown) is adapted to pass air under a predetermined constant pressure into chamber 96, thence through opening 94, the aperture in plug 92, past ball check valve 91 and through bore 87 into the hollow interior of piston rod 60 and against piston 72 when port 88 is sealed by coupling 102 in a manner shown in dotted lines in FIG. 2 and in solid lines in FIG. 1 and bore 88 is closed off by the removable sealing plug 89. The resultant compressed air column in rod 60 acts in the manner of an extended spring and tends to hold the piston 72 in its fully extended or normal operating position shown in FIG. 1 at which time piston 72 is disposed closely adja cent the main actuating piston 62. Since, during the time the piston 72 is in its normal or fully extended position, the tubular connector or coupling 102 used to connect each piston rod 70 to its associated ram 74 remains seated in the central hollowed out section 89 of closure 80 in the fashion shown in FIG. 1. Connector 102 advantageously acts to seal off opening 88 and effect retention of a full air column in the interior of the hollow piston rod 60 so that the air column can act against piston 72 disposed therein and resiliently bias the piston 72 and its rod 70 within the hollow rod 60 of the main actuating piston 62.

When, on the other hand, and as indicated more particularly in FIG. 2, a given ram 74 becomes frozen or hung up in one or more die elements of its associated tool pack assembly C and the main hollow piston rod 60 along with a closure cap 80 is retracted away from such tool pack assembly C, the connector or coupler 102 for such ram will be automatically dislodged from its seat in the hollowed out section 89' of its closure cap 80 and open the vent 88 therein to the atmosphere whereby the biasing of the piston 72 for the given ram is offset as the air column inside of piston rod 60 and on one side of piston 62 becomes fully vented to the atmosphere and collapses. Collapse of this air column produces an effective disconnect or uncoupling of the particular piston 72 in question and its associated rod 70 and rams 74 from the main actuating piston rod 60. Upon collapse of the air column, piston 72 in question will remain in the fixed or stationary position shown in FIG. 2 during the continued operation of the machine and until the operator has time to shut down the machine to unfreeze the disabled ram. During this interim operating period prior to final machine shut down, the disconnected hollow piston rod 60 can continue to freely cycle and slide relative to the inactive piston 72. By virtue of the automatic uncoupling of piston rod 60 when required, as noted above, the machine will not be damaged due to jamming of the parts, something which would otherwise happen unless compensated for by the improved devices of the instant invention. If, for any reason, it is necessary to evacuate air from the interior of piston rod 60, the plug 89 can be manually removed so that the bore 88' can be fully opened to the atmosphere.

With further reference to the drawings, it will be observed that a tool pack assembly C is advantageously supported in a slot S at the enlarged end 106 of each of the cantilevered arms 44. Each tool pack C can be of the same general type as that disclosed and described in copending application Ser. No. 524,637, now Patent No. 3,399,558, filed Feb. 2, 1966, of Langewis et al. and it can be locked to an arm 44 in the same fashion as disclosed in said application. Thus, this tool pack C can comprise one or more redrawing die assemblies 110, each of which is then aligned with its own separate series of ironing die assemblies 112, 114 and 116 together with the appropriate die spacers 120 and container body stripper devices 122, which can be of the type disclosed and described in US. Patent 3,353,394 issued Nov. 21, 1967 to A. D. Smith et al.

The several hollow forming rams 74 connected to one end of a rod 70 are adapted to be simultaneously driven through their various aligned and associated die assemblies 110, 112, 114 and 116 upon the forward stroking of the piston 62 to which rod 70 is coupled along with the shallow cup-shaped blanks X so as to draw and iron these blanks and elongate the same, the blanks having integral bottoms and sidewalls. As the blanks X are forced through the die assemblies by rams 74, they can be successively redrawn and ironed in a known fashion. The blanks are fed through suitable chutes 130 and 131 and into the proper position adjacent the entry end of a redraw die 110 by any suitable feeder means (not shown). All of the die elements and spacers are held in a slot S by suitable locking elements and by a final outer cover 133 in which the various stripper mechanisms 122 can be mounted, the cover 133 being bolted to-the forked sections 106 of end 106 bounding slot S.

As indicated particularly in FIG. 2, bearing sleeves and lock assemblies 140 and plug assemblies 107 are appropriately fitted in the front wall 107 of the slotted and enlarged end portion 106 of each arm 44 for receiving the individual hollow rams 74 tied to the ram coupling member 102 by means of a bridge 142 to which the rams are individually bolted by a series of bolts 143. Each outer cap 82 can be provided with openings 144 and flexible hosing (not shown) connected to a compressed air source can be inserted in these openings 144 and then continued on into the central bores of the hollow rams for the purpose of injecting air through the rarns and against the bottom of the formed container bodies so as to assist in the stripping of the formed container bodies from the ram, if necessary, at the time the formed container bodies are to be stripped from the rams 74. Each outer cap can have a series of wells 144' and well inserts 145 for receiving the rams 74 when the coupling 102 is fully seated in the hollowed out section 89 of a closure cap 80.

It will be noted by further reference to FIGS. 1 and 3 of the drawings that the lower portion of the machine is advantageously equipped with an elongated tube 150 disposed within bores 152 in the lower portions of the outer walls 12 and 14 and openings 154 in the lower portions of the interior ribs 16 and 18. The interior of tube 150 provides a fluid channel or canal that is brought into open communication with one or the other fluid chambers 42 in a manner now to be described.

Tube 150 acts as a convenient dump or bypass reservoir for inactivating the machine in the event an obstruction is placed in the path of advancement of a ram 74 such as a blank X jammed in a cup chute 130 or 131 and which prevents further free forward travel of the ram. When, for example, a ram on the left hand side of the apparatus is obstructed in its forward movement excess hydraulic pressure will build up on the right hand air biased poppet valve assembly 160 at the stepped or chamfered portion 162 of the plunger 163 thereby forcing right hand poppet valve assembly 160 open and effecting a dumping of fluid from right hand chamber 42 into tube 150. It is to be understood that even when both ends of the tube 150 are closed off by closing of each poppet valve assembly 160, a volume of hydraulic fluid fully occupies the interior of the tube 150 between the closed ends thereof, the fluid having been introduced into the tube 150 during initial fluid filling of the equipment. The manner in which the chambers 42 and bypass 150 are initially filled is fully described in applicants copending application Ser. No. 653,950 that was filed concurrently with this application, said copending application of applicants being directed to other advantageous features of the instant apparatus.

The opening of a poppet valve assembly 160 is effected in the following fashion, reference being made particularly to FIG. 3. The plunger 163 is biased outwardly in the valve housing 164 by air introduced from a suitable source through a vent 165 in the housing 164 leading to a chamber 165 in housing 164. The stem element 166 of plunger 163 passes through chamber 165 and when stem 166 is in its normally extended position, the bore 167 therein communicates both with chamber 165' and a further chamber 166' in housing 164 whereby air under pressure can pass through the bore 167 and behind plunger 163 in chamber 166 so as to effect a biasing of plunger 163 against an entrance opening 168 at an end of tube 150. When the excessive hydraulic pressure in a chamber 42 acts on the chamfered section 162 of a valve plunger 163 it overcomes the air pressure against the opposing side of plunger 163 and forces it to retreat into housing 164 at which time the outer end 169 of bore 167 becomes vented to the atmosphere. A plunger 163 is forced 'back into its sealing position adjacent a tube opening 168 by the operator simply grasping plunger stem knob 170 at the proper time and pushing the stem inwardly along with plunger 163 and reestablishing the air flow from chamber 165' to chamber 166' through the bore 167 in stem 166.

The aforesaid build-up of fluid in tube will then cause an opening of left hand air biased poppet valve assembly in the same fashion as right hand valve assembly 160 and both valve assemblies 160 will remain open and allow fluid to surge and circulate back and forth from the chambers 42 into and out of tube 150 rather than into opposing ends of chamber 64 in sleeve 58. When this occurs, there is a pressure drop on each side of piston 62 and piston 62 becomes deactivated, stops and remains in a deactivated condition until the ram obstruction is removed and the closed circuit between chambers 42 and sleeve opening 64 is reestablished by manual operation of the valve assemblies 160. Upon removal of the obstruction from the path advancement of an obstructed ram, the opened right and left poppet valves 160 can be reseated against the openings 168 of tube 150 by the operator suitably grasping the stem knobs thereof and pushing the same inwardly as aforedescribed. Reclosure of the right and left poppet valve assemblies will reestablish the closed fluid circuit between yoke 25 and piston 62. The same result will occur when a ram obstruction occurs on the right hand side of the apparatus as shown in the drawings.

By using the crank mechanism and closed fluid circuit proposed for driving the actuating piston and forming rams, a smooth reliable stroking of the rams through their associated dies is provided. The rams are also positively driven in each direction and are under full control at all times during their forward and backward strokes. The disadvantage of slow acting valves and time lags in the fluid actuating system of US. Patent 3,167,044 is eliminated or minimized. The use of a closed fluid circuit provides for a full balanced movement of the piston 62 relative to yoke 25 and for smooth reliable stroking of all of the rams 74. Smooth and reliable stroking of the rams 74 is particularly important when it is realized that the metal shells or container bodies to be drawn and ironed on the equipment are for the most part only a few thousandths of an inch in thickness and precision draw and ironing is required at all times. Finally, the overall ram driving arrangement proposed provides for efiicient stroking of the press at the high speeds on the order of from 120 to 160 strokes per minute per ram required to meet present day container body production schedules.

Advantageous embodiments of the invention have been disclosed and described. It is obvious that various changes and modifications may be made therein without departing from the spirit and scope thereof as defined by the ap pended claims wherein:

What is claimed is:

1. In a drawn and iron apparatus for forming a container body and the like provided with a bottom and a sidewall formed integrally therewith the combination of a fluid circuit means, piston and rod means disposed in said fluid circuit means, at least one punch means secured to said piston and rod means, means including a resiliently biased piston coupling said punch means to said piston and rod means, at least one die member cooperatively associated with said punch means and through which the punch means is adapted to pass under the urging of said piston and rod means and means for offsetting the resilient bias of said coupling piston and for producing an effective disconnect of said punch means and said piston and rod means upon the punch means becoming lodged and frozen in said die member during passage of the punch means therethrough under the normal urging of the piston and rod means.

2. An apparatus as set forth in claim 1, including means for directing a gaseous fluid against one side of the said coupling piston to effect the biasing thereof.

3. An apparatus as set forth in claim 2 including means for automatically venting the gaseous fluid to the atmosphere when the punch means becomes lodged and frozen in said die member.

4. In a draw and iron apparatus for forming a container body and the like provided with a bottom and a sidewall formed integrally therewith the combination of a fluid circuit means, a first piston and piston rod disposed in said fluid circuit means, at least one punch means coupled to said first piston and piston rod, means coupling said punch means to said first piston and piston rod in cluding a second piston and piston rod telescopingly arranged relative to said first piston rod, said punch means being directly connected to said second piston rod, means resiliently biasing said second piston and rod relative to said first piston rod whereby said second piston and rod will normally remain in a fully extended position relative to said first piston rod during the normal reciprocation of said first piston rod, at least one die member cooperatively associated with said punch means and through which the punch means is adapted to pass under the urging of said first piston and rod, and means for offsetting the resilient bias of said second piston and rod relative to said first piston rod so as to produce an effective disconnect of said punch means and said first piston and rod in the event the punch means becomes lodged and frozen in the said die member during passage of the punch means therethrough under the urging of the first piston and rod.

5. An apparatus as set forth in claim 4 including means for directing a gaseous fluid against one side of the second mentioned piston to effect the biasing thereof relative to said first piston rod.

6. An apparatus as set forth in claim 5 including means for automatically venting the gaseous fluid to the atmosphere when the punch means becomes lodged and frozen in said die member.

7. In a draw and iron apparatus for forming a container body and the like provided with a bottom and a sidewall formed integrally therewith the combination of a fluid circuit means, a piston and a hollow piston rod disposed in said fluid circuit means, at least one punch means coupled to said piston and hollow piston rod, means coupling said punch means to said piston and hollow piston rod including a second piston and piston rod telescopingly mounted within said hollow piston rod with said punch means being directly attached to said second piston rod, fluid gaseous means resiliently biasing said second mentioned piston and piston rod within said hollow piston rod whereby said second mentioned piston and rod will normally remain in a fully extended position within said hollow piston rod during the normal reciprocation of said hollow piston rod, at least one die member cooperatively associated with said punch means and through which the punch means is adapted to pass under the urging of said first mentioned piston and hollow piston rod, means for offsetting the resilient bias of second mentioned piston in said hollow piston rod so as to effectively uncouple the punch means from said first mentioned piston and hollow rod when said punch means becomes frozen in its associated die member during passage of the punch means therethrough under the urging of said first mentioned piston and the piston rod.

8. An apparatus as set forth in claim 7 wherein said last mentioned means includes a vent valve means.

9. An apparatus as set forth in claim 8, wherein a coupling element between said punch means and said second mentioned piston and rod serves to trigger said vent valve means and to open said vent valve means to the atmosphere when said punch means becomes frozen in the die member.

10. In a draw and iron apparatus for forming a container body and the like provided with a bottom and sidewall formed integrally therewith the combination of a closed fluid circuit means, an actuating piston and rod means disposed in one portion of said fluid circuit means and a driving yoke disposed in another portion of said fluid circuit means for actuating the fluid in said circuit means and for reciprocating said actuating piston and rod means, at least one separate punch means secured to each of the opposing sides of said actuating piston and rod means, means including a resiliently biased piston for coupling at least one of said punch means to said actuating piston and rod means, at least one separate die means cooperatively associated with each of said punch means, and means for offsetting the resilient bias of said coupling piston and for producing an effective disconnect of the punch means coupled to the coupling piston and said actuating piston and rod means in the event the last mentioned punch means becomes lodged and frozen in its associated die means during passage of the last mentioned punch means therethrough under the normal urging of the actuating piston and rod means.

11. An apparatus as set forth in claim 10, including means for directing a gaseous fluid against one side of the said coupling piston to effect the biasing thereof.

12. An apparatus as set forth in claim 11 including means for automatically venting the gaseous fluid to the atmosphere when the punch means associated with the coupling piston becomes lodged and frozen in its die means.

13. In a draw and iron apparatus for forming container bodies and the like provided with bottoms and sidewalls formed integrally therewith the combination of a normally closed fluid circuit means, an actuating piston and hollow rod means disposed in one portion of said fluid circuit means and a driving yoke disposed in another portion of said fluid circuit means for reciprocating said actuating piston and hollow rod means, means for actuating said yoke, at least one separate punch means coupled to each of the opposing sides of said actuating piston and hollow rod means, means including a piston and piston rod telescopically mounted within said hollow piston rod means for coupling at least one of said punch means to said actuating piston and hollow rod means, means resiliently biasing said coupling piston and rod within said hollow rod means whereby said last mentioned piston and rod will normally remain in a fully extended position within said hollow rod means during the normal reciprocation of said hollow rod means, at least one die means cooperatively associated with said coupled punch means and means for offsetting the re silient bias of said coupling piston and rod within said hollow rod means and effecting a disconnect of the couping piston and punch means associated therewith from the hollow rod means in the event the said punch means associated with the coupling piston and rod be comes lodged and frozen in its associated die means during passage of the last mentioned punch means therethrough under the urging of the actuating piston and hollow rod means.

14. In a draw and iron apparatus as set forth in claim 13 including means for directing a gaseous fluid against one side of the said coupling piston to effect the biasing thereof in said hollow rod means.

15. An apparatus as set forth in claim 14 including means for automatically venting the gaseous fluid to the atmosphere when the punch means associated with the coupling piston becomes lodged and frozen in its die means.

16. In a draw and iron apparatus for forming a container body and the like provided with a bottom and a side wall formed integrally therewith the combination of a normally closed fluid circuit means, an actuating piston and rod means disposedin one portion of said closed fluid circuit means, a driving yoke disposed in another portion of said closed fluid circuit means for acting on the fluid in said circuit means and for reciprocatingsaid actuating piston and rod means, at least one separate punch means coupled to each of the opposing sides of said actuating piston and rod means, at least one die means cooperatively associated with each of said punch means, means for continuously actuating said driving yoke and a fluid bypass for said normally closed fluid circuit means and connectable to said circuit means so as to effect a short circuiting of the fluid in said circuit means and a stoppage of the actuating piston and rod means when the forward movement of a given punch means coupled to said actuating piston and rod means is obstructed.

17. An apparatus as set forth in claim 16 including poppet valve means for connecting said fluid bypass to said fluid circuit means when excess pressure builds up in a given portion of the fluid circuit means due to an obstruction in the path of a punch means.

18. In a draw and iron apparatus for forming a container body and the like provided with a bottom and a side wall formed integrally therewith the combination of a normally closed fluid circuit, an actuating piston and rod means disposed in one portion of said closed fluid circuit, a driving yoke disposed in another portion of said closed fluid circuit for acting on the fluid in said circuit and for reciprocating said actuating piston and rod means, at least one separate punch coupled to each side of said actuating piston and rod means, at least one die means cooperatively associated with each of said punches, power means for continuously driving said yoke, a fluid filled reservoir connectable to selected portions of said circuit on opposite sides of said yoke, valve means normally sealing said reservoir off from communication with said fluid circuit and means responsive to excessive resistance on either side of said actuating piston and rod means during the reciprocation thereof for opening said valve means to transfer fluid pressure from the portion of the fluid circuit containing said actuating piston and.

rod means to a further portion of the fluid circuit so as to substantially instantaneously arrest the reciprocation of said actuating piston and rod means.

19. In a draw and iron apparatus for forming a container body and the like provided with a bottom and a side wall formed integrally therewith the combination of a normally closed fluid circuit means, an actuating piston and rod means disposed in one portion of said closed fluid circuit means, a driving yoke disposed in another portion of said closed fluid circuit means for acting on the fluid in said circuit means and for reciprocating said actuating piston and rod means, at least one separate punch means coupled to each of the opposing sides of said actuating piston and rod means, at least one die means cooperatively associated with each of said punch means, means for continuously actuating said driving yoke and means resiliently biasing at least one of said punch means relative to said actuating piston and rod means.

20. An apparatus as set forth in claim 18 wherein the means responsive to excessive resistance on either side of said actuating piston and rod means comprises a fluidically biased valve actuator.

21. An apparatus as set forth in claim 18 wherein said valve means comprises a plurality of valves, with a separate valve being located at each of the opposing ends of said reservoir. 1

References Cited UNITED STATES PATENTS 2,766,590 10/1956 Erwin 54.5 3,167,044 1/1965 Henrickson 60-54.5 3,314,274 4/ 1967 Langewis 72349 3,353,394 11/1967 Smith 72-347 CHARLES W. LANHAM, Primary Examiner G. P. CROSBY, Assistant Examiner U.S. Cl. X.R. 72-347, 354 

